With increasing power of personal computers, a diversity of peripheral devices can be employed with the personal computers to achieve various purposes. The diverse peripherals, however, occupy lots of space and I/O ports of a computer. A multifunction peripheral having multiple functions in one structural unit is thus developed, for example the functions of a printer, a scanner, and optionally a fax machine and/or a copy machine. FIG. 1 is a side view schematically showing a multifunction peripheral. The multifunction peripheral 1 comprises a scanner portion 10 and a printer portion 11. A hinge device 12 is arranged between the scanner portion 10 and the printer portion 11. By pivoting up the scanner portion 10 about the hinge device 12, the printer portion 11 can be exposed to replace the cartridge accommodated in the printer portion 11 or remove a stuck paper. The hinge device 12 not only serves a pivoting fulcrum but also provides a lift-up force to facilitate the pivoting operation. The mechanism of the hinge device 12 will be described hereinafter with reference to FIG. 2.
As shown in FIG. 2, the hinge device 12 comprises a connecting portion 22 screwed to the printer portion 11. The scanner portion 10 is connected to the connecting portion 22 and pivotal about the fulcrum 21. The hinge device 12 also comprises an auxiliary spring 20 urging against between the connecting portion 22 and a cover portion of the multifunction peripheral, i.e. the scanner portion 10. The recovering force to spontaneously recover itself to a released or uncompressed state provides an auxiliary force to help lift the scanner portion 10 up. For example, when the spring 20 is recovered to its original released or uncompressed state, the scanner portion 10 is lifted upright. From the above description, it is inherent that when the scanner portion 10 is at a closed position lying on the printer portion 11, which indicates a normal operational state of the multifunction peripheral and is so for most time, the spring 20 is compressed. Meanwhile, the compressed spring 20 imparts an urging force against the connecting portion 22. Comparable to the auxiliary force for lifting up the scanner portion, the urging force of the spring against the connecting portion 22 is also strong. Therefore, the associated components are subject to being loosened or even stripped.